Theron has said she was drawn to the character because she wasn’t like any she had ever seen before.

“I hadn’t seen another character like her out there,” Theron explained in an interview with Entertainment Weekly. “She doesn’t apologize for anything. We made her strong and feisty.”

“Let’s be honest, I got my ass handed to me every day,” she added. “I cracked through two of my teeth in the back of my mouth from clenching so much that I had to have massive dental surgery right before we left for Budapest to shoot the film.”

The film, based off the book by Antony Johnston “The Coldest City,” hits theaters July 28th.